DANVILLE — On a recent sunny, 50-degree morning, 70 students from The Athenian School discovered an activity better than speed-reading, speed-texting or speed-dating — speed-planting.

In less than 50 minutes, an unused, steeply-pitched hillside on the 75-acre campus went from scraggly to stupendous as 125 fruit trees became an orchard.

Working in teams of two after receiving a brisk, CliffsNotes-style agricultural lesson — one holds tree, other shovels dirt, knot stays above soil or tree will die — students happily explained why they were excited to participate.

Her partner, Simone Batiste, 15, from Oakland, agreed. She had felt hunger’s pain during a 40-hour fast undertaken last fall to raise awareness.

“When I connected to the purpose; the pain stopped, because the cause was worth it,” she said.

More than earning “A’s” in the community service projects that the college preparatory school requires of all students, altruism also fertilized the enthusiasm of Pierson Tan, who spearheaded the project.

“I’ve always had an interest in environmental conservation,” he said. “In eighth grade, I planted saplings, and I remember thinking, ‘These trees will be here a lot longer than I will.’ And also, there are people starving, even here in the Bay Area. That’s most important to me — not sending food off to faraway countries but helping people right here.”

Taking his initial, modest idea (to supervise eight 10th-grade students as they planted 10 trees), Tan worked with history teacher Matt Zahner to put his feed-the-locals project into action.

The swift and secret sauce that brought together stick-sized trees and stone-shaped clumps of dirt to break the bonds of hunger and build an orchard came from Siamack Sioshansi’s The Urban Farmers, an East Bay all-volunteer nonprofit devoted to eradicating hunger (primarily through tree planting and fruit and vegetable gleaning). Urban Farmers donates all harvested produce to Bay Area food banks.

“He just kept showing up,” Zahner said, about Sioshansi. “Our mission of environmental responsibility and commitment to service dovetailed with his. It all fit perfectly.”

The young apple, pear, olive and fig trees planted at Athenian will not bear fruit until 2016 and beyond. After Sioshansi told the students each tree would deliver up to 100 pounds of fruit, the subsequent math was cause for celebration; wiping out any complaints about the delayed gratification.

“At 125 trees, that’s 12,500 pounds,” Sioshansi explained. “A farmer can grow five pounds of food, any food, to feed one person for one day. You will be growing a banquet for 2,500 people — enough to feed them breakfast, lunch and dinner for the next 50 years.”

William Brown, 16, of Danville, mentioned another silver lining of the project: re-purposed water.

“The orchard will catch the runoff from the baseball field above, so we won’t have to do as much irrigation. There are no losers — everyone wins!” he exclaimed.

Lakin Moser, 17, said he sees “both sides of the hunger coin” where he lives in Oakland. His father is active in the nonprofit Opportunity International, so Third World poverty is frequently discussed at the dinner table.

“Every time you look at it, it’s still shocking. But because of that, I don’t take as much for granted,” he said.

Perception, as much as dirt, was shifted for Noah Lourie, 17, of Berkeley.

“This has taught me that poverty isn’t necessarily defined by a person who is inept. It’s more defined by the situation they’re in. Being in a position of privilege, it’s our responsibility to help people who aren’t in a good place,” Laurie said.

Standing on the hill above the young farmers, Sioshansi was proud. He said the 12,500 pounds of fruit the orchard will eventually produce will be donated to The Food Bank of Contra Costa and Solano Counties and to Monument Crisis Center. Inedible fruit that falls to the ground will go the Lindsay Wildlife Hospital.

But his satisfaction was fleeting.

“All the schools have fields like this,” he claimed. “They need to wake up to students’ and parents’ concern about food, environment, hunger. Schools say, ‘Kids might get sick,’ and ‘Kids will throw fruit, and we’ll get sued.’ You have to have a vision to fill a vacuum of need.”

Tan, nearly finished with his speed-planting, dared to dream, saying, “I have a little brother, so I hope when he’s a junior, he’ll be part of picking the harvest and sharing the fruit.”